Chilon Library is a C++0x utility library. The most advanced parts are a command-line argument parser and a parser generator library based on parsing expression grammars with built in AST generation abilities.
There are a few other cool parsing expression grammar libraries out there like pegtl. What makes this one different is its ability to automatically construct the AST of a language based on the grammar description. chilon::parser is based on the TBPEG variant of PEG notation, which is discussed in this paper.